Year	Number
1960	0
1965	0
1970	0
1975	0
1976	0
1977	0
1978	0
1979	0
1980	0
1981	0
1982	0
1983	0
1984	0
1985	0
1986	0
1987	0
1988	0
1989	0
1990	0
1991	559
1992	988
1993	1260
1994	1813
1995	2534
1997	4109
1998	5170
1999	8410
2000	10700
2001	17000
2002	19000
2003	21040
2004	33800
2005	80945
2006	92559
2007	101497
2008	98313
2009	108699
2010	100568
2011	96777
2012	98834
2013	98036
2014	91059
2015	93244
2016	95656
2017	96656
2019	99000
2020	100000
2021	100000